package net.minecraft.world.level.levelgen;

import net.minecraft.SharedConstants;
import net.minecraft.util.Mth;
import net.minecraft.util.RandomSource;
import net.minecraft.world.level.block.Blocks;
import net.minecraft.world.level.block.state.BlockState;

public final class OreVeinifier {
	private static final float VEININESS_THRESHOLD = 0.4F;
	private static final int EDGE_ROUNDOFF_BEGIN = 20;
	private static final double MAX_EDGE_ROUNDOFF = 0.2;
	private static final float VEIN_SOLIDNESS = 0.7F;
	private static final float MIN_RICHNESS = 0.1F;
	private static final float MAX_RICHNESS = 0.3F;
	private static final float MAX_RICHNESS_THRESHOLD = 0.6F;
	private static final float CHANCE_OF_RAW_ORE_BLOCK = 0.02F;
	private static final float SKIP_ORE_IF_GAP_NOISE_IS_BELOW = -0.3F;

	private OreVeinifier() {
	}

	static NoiseChunk.BlockStateFiller create(
		final DensityFunction veinToggle,
		final DensityFunction veinRidged,
		final DensityFunction veinGap,
		final PositionalRandomFactory oreVeinsPositionalRandomFactory
	) {
		BlockState defaultState = SharedConstants.DEBUG_ORE_VEINS ? Blocks.AIR.defaultBlockState() : null;
		return context -> {
			double oreVeininessNoiseValue = veinToggle.compute(context);
			int posY = context.blockY();
			OreVeinifier.VeinType veinType = oreVeininessNoiseValue > 0.0 ? OreVeinifier.VeinType.COPPER : OreVeinifier.VeinType.IRON;
			double veininessRidged = Math.abs(oreVeininessNoiseValue);
			int distanceFromTop = veinType.maxY - posY;
			int distanceFromBottom = posY - veinType.minY;
			if (distanceFromBottom >= 0 && distanceFromTop >= 0) {
				int distanceFromEdge = Math.min(distanceFromTop, distanceFromBottom);
				double edgeRoundoff = Mth.clampedMap((double)distanceFromEdge, 0.0, 20.0, -0.2, 0.0);
				if (veininessRidged + edgeRoundoff < 0.4F) {
					return defaultState;
				} else {
					RandomSource positionalRandom = oreVeinsPositionalRandomFactory.at(context.blockX(), posY, context.blockZ());
					if (positionalRandom.nextFloat() > 0.7F) {
						return defaultState;
					} else if (veinRidged.compute(context) >= 0.0) {
						return defaultState;
					} else {
						double richness = Mth.clampedMap(veininessRidged, 0.4F, 0.6F, 0.1F, 0.3F);
						if (positionalRandom.nextFloat() < richness && veinGap.compute(context) > -0.3F) {
							return positionalRandom.nextFloat() < 0.02F ? veinType.rawOreBlock : veinType.ore;
						} else {
							return SharedConstants.DEBUG_ORE_VEINS ? Blocks.OAK_BUTTON.defaultBlockState() : veinType.filler;
						}
					}
				}
			} else {
				return defaultState;
			}
		};
	}

	protected static enum VeinType {
		COPPER(Blocks.COPPER_ORE.defaultBlockState(), Blocks.RAW_COPPER_BLOCK.defaultBlockState(), Blocks.GRANITE.defaultBlockState(), 0, 50),
		IRON(Blocks.DEEPSLATE_IRON_ORE.defaultBlockState(), Blocks.RAW_IRON_BLOCK.defaultBlockState(), Blocks.TUFF.defaultBlockState(), -60, -8);

		private final BlockState ore;
		private final BlockState rawOreBlock;
		private final BlockState filler;
		protected final int minY;
		protected final int maxY;

		private VeinType(final BlockState ore, final BlockState rawOreBlock, final BlockState filler, final int minY, final int maxY) {
			this.ore = ore;
			this.rawOreBlock = rawOreBlock;
			this.filler = filler;
			this.minY = minY;
			this.maxY = maxY;
		}
	}
}